This invention relates generally to voltage sources, such as batteries, for any of a variety of applications including operating a processor-based system.
Conventionally, battery powered or portable processor-based systems utilize a battery power source whose output is controlled by a voltage regulator. The voltage source may be made up of a plurality of batteries as one example. Because the equipment being powered, such as a processor-based system, may demand a particular input voltage and because that voltage requirement may vary during operation, typically voltage sources use a regulator to hide the variances of the voltage source due to battery discharge, for example.
Voltage regulators are somewhat inefficient because they dissipate some power in the course of regulating the voltage. Some types of regulators may change their output voltages on the fly, but those types of regulators are inherently linear operating regulators and require extra circuits for a digital control. In addition, regulators may require a relatively long time to change the output voltage. In some cases, switching voltage regulators may emit radio frequency interference (RFI) and so may need some type of RFI shielding.
Thus, there is a need for better ways to control the output voltage of a plurality of voltage sources.